Connecting-system kit for a respiratory humidifier

ABSTRACT

A liquid-container/ventilation-tube kit for a ventilation system that includes (a) a ventilator, (b) a respiratory humidifier having a housing and a liquid container, the housing having a pair of first electrical contact elements, (c) a first inhalation tube extending from the respiratory humidifier to a Y-piece, (d) a second inhalation tube extending from the ventilator to the respiratory humidifier, and (e) an exhalation tube extending from the Y-piece to the ventilator, the kit including the liquid container having a pair of first connection elements for removable connection of the first and second inhalation tubes thereto, and a pair of second connection elements each attached to a respective one of the first and second inhalation tubes and by which each of the inhalation tubes is pneumatically connected to a respective one of the first connection elements along a first connecting direction, each second connection element having a second electrical contact element that is positioned and arranged such that electrical connection with a respective one of the first electrical contact elements is possible in both of two ways, one when the pneumatic connection of the respective ventilation tube to the liquid container is effected after the liquid container has been inserted into the housing and the other when the liquid container is inserted into the housing after the pneumatic connection of the ventilation tubes to the liquid container has been effected.

RELATED APPLICATIONS

This is a continuation of Ser. No. 14/348,969, filed Apr. 1, 2014, whichwas based on PCT/EP2012/069125, filed Sep. 27, 2012, which claimspriority to German Patent Application No. DE 10 2011 054 134.9, filedOct. 1, 2011, the contents of which are incorporated by reference intheir entireties.

FIELD OF INVENTION

The present invention relates to respiratory humidifiers for ventilationof patients with breathing gas, and more specifically to connectingsystems for respiratory humidifiers.

BACKGROUND OF THE INVENTION

When patients are being mechanically ventilated on an intensive-careward, for example, the patient to be ventilated is connectedpneumatically to the ventilator or respirator by a system of ventilationtubing. Because the breathing gas supplied to the patient must beadjusted with respect to temperature and humidity to meet thephysiological needs of the patient, a respiratory humidifier is arrangedin the inhalation or inspiration tube to heat and humidify the breathinggas. The respiratory humidifier comprises a liquid container filled withdistilled water, through which the breathing air is conducted andhumidified.

To prevent moisture from condensing inside the system of ventilationtubing, the inhalation tube and expiration or exhalation tube areusually provided with electrical tube heaters to heat the flowinginhalation or exhalation gas during operation. Loops of heating wire,for example, are used, which are integrated into the inhalation andexhalation tubes, or the inhalation and exhalation tubes are wrappedwith coils of heating wire.

The breathing air temperature is usually regulated by means of atemperature sensor arranged near the patient; the sensor is connected bymeans of an electrical measurement line to a control unit, which isinstalled in the respiratory humidifier, for example. It is thereforelogical to design the electrical contact elements of the electricallines on the tube connectors jointly with the pneumatic connectionelements in order to minimize the number of separate connections.

Pneumatic tube couplers with electrical contact elements integrated intothem are described in, for example, EP 1 127 583 A2; DE 199 58 296 C1;DE 197 25 875 A1; and US 2003/0059213 A1. A system which connects thetwo functional components of the inhalation tube to the respiratoryhumidifier is known from EP 1 369 141 A1. The connection element or tubecoupler comprises a male plug section on the liquid container of therespiratory humidifier, onto which a female sleeve section at the end ofthe inhalation tube can be placed. Electrical contact elements arearranged laterally on the sleeve section of the inhalation tube; whenthe sleeve section is placed on the plug section, these elements arebrought into contact with another electrical contact on the housing ofthe respiratory humidifier to establish the electrical connection.

The disadvantage of the tube connecting system described in EP 1 369 141A1 is that it can be placed onto the respiratory humidifier in only onedirection, namely, from above. Before the connection is made, theelectrical contact elements on the housing project awkwardly from thehousing as independent elements and thus interfere with the appearanceand practicality of the respiratory humidifier. Another disadvantagearising from this connecting system is that it limits the scope ofpossibilities for designing the respiratory humidifier. Logicalimprovements in this regard are therefore almost impossible to make withthe existing devices.

It is therefore the object of the present invention to provide aconnecting system for connecting a ventilation tube to a respiratoryhumidifier, which system offers a variety of ways in which theelectrical contact elements can be connected to each other and whichthus makes it possible to improve the design and appearance of therespiratory humidifier. It is also an object of this invention toprovide a convenient kit including the liquid container and the tubinghaving such advantages.

SUMMARY OF THE INVENTION

According to one aspect of the invention, a connecting system forconnecting a ventilation tube to a respiratory humidifier is provided,wherein the ventilation tube comprises an electrical line and therespiratory humidifier comprises a housing and a liquid container, theconnecting system including a first connection element arranged on theliquid container, a first electrical contact element arranged on thehousing, a second connection element, which can be connected to theventilation tube, and a second electrical contact element, which can beconnected to the electrical line of the ventilation tube, wherein thefirst connection element and the second connection element can beconnected to each other in a first connecting direction in such a waythat, through the establishment of the pneumatic connection of theventilation tube with the liquid container, the electrical connection ofthe first contact element with the second contact element is alsoachieved.

The connection system is characterized in that the electrical connectionof the first contact element with the second contact element can beestablished in a second connecting direction different from the firstconnecting direction, preferably in a direction essentiallyperpendicular to the first connecting direction. This offers theadvantage that the liquid container with the ventilation tube or withseveral ventilation tubes connected to it can be slid sideways, forexample, into the housing of the respiratory humidifier, which thusfacilitates a compact design for the respiratory humidifier.

It should be noted here that the tubing and connecting systems and theliquid containers for ventilators used in hospitals are frequentlydesigned as single-use or disposable articles, and it is thereforelogical to provide as many of the connections as possible on thesingle-use parts, so that the operating personnel are required toperform only a small number of connection procedures. As a result, theoperating time is significantly reduced, and the risk of connecting thecomponents improperly is minimized. In the situation present before theliquid container and the ventilation tube are connected together, theinventive connecting system offers the possibility of connecting thetube before or after the liquid container has been inserted into thehousing of the respiratory humidifier. The lateral insertion of theliquid container/ventilation tube kit thus opens up the possibility ofnew and advantageous design alternatives.

The first and second connection elements are preferably tubular indesign and comprise a circular cross section. The first and secondconnection elements are preferably able to slide axially into each otherin the first connecting direction. It is obvious that the circular crosssection pertains essentially to the pneumatic connection between theventilation tube and the liquid container. At least certain parts of theelectrical contact elements are then arranged around this cross section.Other cross-sectional shapes such as rectangular, elliptical, orpolygonal, are also possible.

It is also advantageous for the second connection element to comprise anexternal projection, which engages for guidance in a recess in the firstconnection element or in the housing of the respiratory humidifier. Theventilation tube and the liquid container can thus be connected to eachother in a previously determined manner, namely, in a manner determinedby the guide elements. It is possible to arrange several guides on thecorresponding elements. It has been found adequate, however, andespecially effective to provide exactly one guide element per connectingsystem.

It is also preferable for each of the first and second electricalcontact elements to comprise a plurality of electrical contacts. It isadvisable here for the first and second contact elements to have thesame number of electrical contacts. It has been found that sixelectrical contacts per electrical contact element offer sufficientopportunities for transmitting electrical heating power, data, andmeasurement values, for example, via the ventilation tube system.

It is especially advantageous for the establishment of the properpneumatic and electrical connections between the first and secondconnection elements to result in the closure of an electrical signalpathway. Thus the fact that all of the connections have been properlyestablished can be displayed on the display device, for example, of therespiratory humidifier. Alternatively, other types of optical and evenacoustic signals are also possible.

The first electrical contact element preferably comprises recesses, intowhich mating projections of the second electrical contact element engagein order to establish the electrical connection. The recesses andprojections will thus be located next to each other, will be accessiblefrom two directions, i.e., from above and from the side, and cancomprise different materials and dimensions, depending on the power tobe transmitted or the stability of the electrical contact connection. Ina similar manner, the electrical contact elements can be provided withone or more springs.

It is advantageous for the ventilation tube to comprise a plurality ofelectrical lines, wherein preferably (at least) one is designed as aheating wire loop or heating wire coil, a power supply line, ameasurement line, or a data line. Thus it is also possible not only fordata or signals to be evaluated in the respiratory humidifier but also,for example, for signals to be sent from the patient to the respiratoryhumidifier or vice versa.

Also according to an aspect of the invention is a ventilation systemcomprising a ventilator, a first inhalation tube, a second inhalationtube, a respiratory humidifier, and two connecting systems as describedabove, wherein the two connecting systems connect the first and secondinhalation tubes to the respiratory humidifier.

It is especially advantageous that the first inhalation tube and thesecond inhalation tube can be connected by the use of either the firstor the second connecting system, wherein the flow direction of thebreathing gas can be recognized on the basis of the electrical contactelements. The respiratory humidifier can be thus be used flexibly, forit recognizes where the inhalation tube leading to the ventilator, i.e.,to the source of the breathing air, is connected and then determines onthis basis the direction in which the breathing air should flow throughthe respiratory humidifier. Operating errors by the user are thusfurther reduced, because reversing the connection of the inhalationtubes no longer leads to a malfunction.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is to be explained below on the basis of exemplaryembodiments with reference to the attached figures:

FIG. 1 is a schematic diagram of one embodiment of the ventilationsystem according to the present invention;

FIG. 2 is a perspective view of a liquid container with parts of apreferred embodiment of the connecting system according to theinvention;

FIG. 3 is a perspective view of an inhalation tube with parts of thepreferred embodiment of the connecting system according to theinvention;

FIG. 4 is a perspective view of a housing of a respiratory humidifierwith parts of the preferred embodiment of the connecting systemaccording to the invention;

FIG. 5 is an enlarged detail of FIG. 4;

FIG. 6 is a perspective view of a respiratory humidifier with twoconnecting systems according to the preferred embodiment;

FIG. 7 is a perspective view of a respiratory humidifier illustratingthe first connecting direction according to the invention; and

FIG. 8 is a perspective view of a respiratory humidifier illustratingthe second connecting direction according to the invention.

DETAILED DESCRIPTION

FIG. 1 schematically shows a preferred embodiment of a ventilationsystem having a connecting system according to the invention. Arespiratory humidifier 1 is arranged between a respirator 3 and aY-piece 5 and connected to them by a first inhalation or inspirationtube 7 and a second inhalation or inspiration tube 9. The simplydesigned end of the Y-piece 5 is pointing toward the patient to beventilated, as indicated by the arrow. Finally, an exhalation orexpiration tube 11 is arranged between the respirator 3 and theremaining end of the Y-piece 5.

A flow of dry breathing gas is produced by a blower (not shown), forexample, in the respirator 3; this gas leaves the ventilator through thefirst inhalation tube 7 and proceeds toward the respiratory humidifier1. There the breathing gas is conducted in the known manner into aliquid container (not shown in FIG. 1), where it is heated andhumidified by the heated liquid. The heated and humidified breathing gasleaves the respiratory humidifier 1 via the second inhalation tube 9 andis supplied to the patient via the Y-piece 5.

In accordance with a breathing cycle controlled by the respirator 3, thespent breathing air flows back from the patient, enters the exhalationtube 11 at the Y-piece 5, and returns to the respirator 3.

A heating wire 13 is integrated into the wall of the second inhalationtube 9; this wire is wound into a spiral and serves as a heating coil.Also integrated into the second inhalation tube 9 is an electricalmeasuring line 15, which transmits the signal from a temperature sensor17 arranged at the end near the Y-piece 5 to the control unit (notshown) of the breathing air humidifier 1. The location of thetemperature sensor 17 is selected so that it is as close as possible tothe patient but is still a part of the ventilation tube system, which isdesigned to be as easy as possible to replace.

The pneumatic and electrical connections of the second inhalation tube 9to the respiratory humidifier 1, that is, the inhalation gas connectionand the connections of the heating wire 13 and the measurement line 15,are achieved by means of a first connecting system 19.

The exhalation tube 11 also comprises a tube heater in the form of theheating wire 21, which is also wound into a spiral to form a heatingcoil. The reason for heating the exhalation tube 11 is to prevent thebreathing gas returning from the patient from condensing in theexhalation tube 11 and flowing as contaminated liquid, for example, backto the patient through the Y-piece 5. The tube heater of the exhalationtube 11 can be continuous or be formed in sections. The heating wire 21is supplied with current through a power supply line 23, which startsfrom the respiratory humidifier 1 and proceeds via a second connectingsystem 25, the first inhalation tube 7, and a connection element 27 tothe exhalation tube 11. The second connecting system 25 thus representsthe pneumatic and electrical connection of the first inhalation tube 7to the respiratory humidifier 1, that is, the inhalation gas connectionand the connection of the power supply line 23.

FIG. 2 shows a perspective view of a liquid container 4 with parts of apreferred embodiment of the connecting system according to theinvention. The liquid container 4 comprises two first connectionelements 6, which are arranged at the sides of the upper section.Between the two connection elements 6 a recess is formed, which isdesigned to mate with the housing projection (not shown in FIG. 2), sothat the container can be pushed into the housing around the projection,as shown in FIGS. 4-7. The first connection elements 6 are designed asprojecting tubular sockets with a circular cross section, but they mayalso have an elliptical or polygonal or even rectangular cross section.

A short distance away from each of the first connection elements 6, thatis, at a distance sufficient to allow the second connection elements 14to be pushed on, there is a guide 8, which serves to align the secondconnection element 14 axially so that it can be pushed easily onto thefirst connection element 6. It can also be seen that the firstconnection elements 6 do not project beyond the edge of the liquidcontainer 4. This offers the advantage that they are less susceptible todamage if the liquid container 4 were to fall onto its back or top. Arefill tube 10 is connected to the liquid container 4 by a suitableconnecting piece. Because the internal volume of the liquid container 4is limited, fresh water is supplied through the refill tube 10 when thewater in the interior of the liquid container 4 falls below a certainlevel. The material of the liquid container 4 is a suitable transparentplastic such as polyethylene (PE) or polypropylene (PP). Other suitableplastic materials can also be used, however.

FIG. 3 shows a perspective view of an inhalation tube 9 with parts ofthe preferred embodiment of the connecting system according to thepresent invention. One end of the first inhalation tube 9 forms aconnecting piece; the end of this connecting piece facing way from thetube is formed by the second connection element 14. The connecting piecealso comprises a second electrical contact element 16, which is arrangedon one side of the connecting piece. It is equipped with electricalcontacts, which are designed as projections 18. The connecting piecealso comprises gripping elements 20, which are also located on thesides, namely, about 901 away from the second electrical contact element16, and which serve as points where force can be exerted to separate theconnection. On the side opposite the second electrical contact element16, the second connection element 14 comprises an elongated projection12 on the outside surface, which extends in the axial direction andwhich is able to engage in the guide 8, which is shown in FIG. 2. Toachieve a design which is attractive in both an optical and hapticsense, the connecting piece comprises a slanted skirt, which, when theconnecting system is in the assembled state on the liquid container 4,is intended to create an essentially closed covering surface.

In the preferred embodiment, the second connection element 14 is pushedall the way onto the first connection element 6 along the guide; thatis, it is pushed with a press fit all the way down until it rests on theliquid container 4, which acts as a stop. Alternatively, a latchingmechanism can be arranged between the two connection elements 6, 14,which can be released again by pressing on the gripping elements 20, forexample.

FIG. 4 shows a perspective view of a housing 2 of a respiratoryhumidifier 1 with parts of the preferred embodiment of the connectingsystem according to the present invention. The housing 2 has essentiallythe shape of an “L” with a horizontal part and a vertical part andcomprises a heating plate on the horizontal part, which serves to heatthe liquid in the liquid container 4 (not shown in FIG. 4). Extendingfrom approximately the middle of the free end of the vertical part, thehousing 2 comprises a slanting, projecting section, which comprises auser interface 22, provided with a display unit and operating elements.The interior of the housing 2 comprises, among other things, a controlunit, which is able, for example, to regulate the output of the heatingplate on the basis of the signals received from various temperaturesensors. The housing 2 can also comprise other functional elements notbelonging to the scope of the present invention. At the sides of theupper area of the vertical section of the housing 2, first electricalcontact elements 24 are formed, which fit together with the secondelectrical contact elements 16 on the connecting piece shown in FIG. 3.

FIG. 5 shows an illustration on an enlarged scale of the upper rightarea of FIG. 4. It can be seen that the first electrical contact element24 is arranged at the upper end of an essentially vertical housing walland is set into a notch, wherein the electrical contacts are formed byrecesses 26, which mate exactly with the projections 18 of the secondelectrical contact element 16 (see FIG. 3). It can be derived from ajoint consideration of the electrical contact elements 16 and 24 asshown in FIGS. 3 and 5 that the electrical connection between theconnecting piece of FIG. 3 and the housing 2 of FIG. 4 can occur both byinsertion from the top and also by lateral insertion in the horizontaldirection.

FIG. 6 shows a perspective view of a respiratory humidifier with twoinventive connecting systems according to the preferred embodiment ofthe present invention. The object of FIG. 6 can be seen in thecombination of the liquid container 4 of FIG. 2 with the tube connectingpiece of FIG. 3 (two of which are present) and the housing 2 shown inFIG. 4. The liquid container 4 here has been pushed horizontally intothe open area of the housing 2, so that the bottom section of the liquidcontainer 4 lies essentially on the lower section of the housing 2,where the heating plate of the respiratory humidifier 1 is located. Aconnecting piece, one of which is located at the end of each of the twoinhalation tubes 7, 9, is pushed onto each of the two first connectionelements 6.

In the situation present before the liquid container 4 has beeninstalled in the housing 2, the only effect of setting the secondconnection element 14 onto the opposing part, namely, the firstconnection element 6, so that the projection 12 fits within the guide 8,is that of establishing the pneumatic connection between the tube andthe liquid container 4. The electrical connection between the electricalmeasurement, heating, or data lines in the tubes 7, 9 and the housing 2can be established in either of two different ways.

The first possibility is to insert the liquid container 4 into thehousing 2 and then to put the tubes 7, 9 in place by means of theconnecting system, as a result of which the pneumatic and electricalconnections are established simultaneously as seen in FIG. 7. Theconnecting direction in this case is vertically from above, in the axialdirection of the ends of the tubes.

The second possibility, illustrated in FIG. 8, will be used morefrequently in cases where the ventilation tube systems are designed assingle-use/disposable articles, because the liquid container 4 willusually be delivered together with a complete ventilation tube system,that is, together with the first inhalation tube 7, the secondinhalation tube 9, and the exhalation tube 11 and possibly the Y-piece 5(see FIG. 1), all connected together as a unit, so that the operatingpersonnel are required to perform the minimum number of connectingsteps. To connect the liquid container 4 to the housing 2 of therespiratory humidifier, the liquid container is inserted into thehousing 2 horizontally, that is, in a direction perpendicular to thedirection of the tubing and to the direction in which the pneumaticlines are connected. The liquid container 4 and the housing 2 aredesigned in such a way that the liquid container 4 latches in place in amanner which is perceptible to the user. FIG. 6 shows the latched endposition of the liquid container 4 in the housing 2, and when the liquidcontainer 4 latches itself in place in the housing 2, the electricalconnection between the second electrical contact element 16 of theconnecting pieces 7, 9 with the corresponding opposing pieces of thefirst electrical contact elements 24 is also established. Once all ofthe electrical and pneumatic connections have been properly established,the control unit can emit an acoustic signal or display the status onthe user interface 22.

With the subject matter of the present invention, a connecting systemfor connecting a ventilation tube to a respiratory humidifier has beenprovided which offers flexible design possibilities for the electricalcontact elements and thus enables an improved design as well as anattractive appearance of the respiratory humidifier. It should also bepointed out here that the connecting system according to the inventioncan also be used in principle to connect the second end of the firstinhalation tube to the ventilator or also to connect the exhalation tube11 to the respirator 3.

The invention claimed is:
 1. A liquid-container/ventilation-tube kit fora ventilation system that includes (a) a ventilator, (b) a respiratoryhumidifier having a housing and a liquid container, the housing having apair of first electrical contact elements, (c) a first inhalation tubeextending from the respiratory humidifier to a Y-piece, (d) a secondinhalation tube extending from the ventilator to the respiratoryhumidifier, and (e) an exhalation tube extending from the Y-piece to theventilator, the liquid-container/ventilation-tube kit comprising: theliquid container having a pair of first connection elements forremovable connection of the first and second inhalation tubes thereto;and a pair of second connection elements each attached to a respectiveone of the first and second inhalation tubes and by which each of theinhalation tubes is pneumatically connected to a respective one of thefirst connection elements along a first connecting direction, eachsecond connection element having a second electrical contact elementconnected to an electrical line extending along the respectiveinhalation tube, each second electrical contact element being positionedand arranged such that electrical connection with a respective one ofthe first electrical contact elements is possible in both of two ways,including: (i) in the first connecting direction when the pneumaticconnection of the respective ventilation tube to the liquid container iseffected after the liquid container has been inserted into the housingand (ii) by movement of the liquid container in a directionperpendicular to the first connecting direction when the liquidcontainer is inserted into the housing after the pneumatic connection ofthe ventilation tubes to the liquid container has been effected.
 2. Thekit of claim 1 wherein the first and second connection elements aretubular with circular cross-sections and are slideably interengageableby relative axial motion thereof in the first connecting direction. 3.The kit of claim 2 wherein the second connection element comprises anexternal projection configured and arranged for engagement in a recessin the first connection element or in the housing of the respiratoryhumidifier to guide the connection of the second and first connectionelements.
 4. The kit of claim 1 wherein the first and second electricalcontact elements each comprise a plurality of electrical contacts. 5.The kit of claim 4 wherein the first and second electrical contactelements each include six electrical contacts.
 6. The kit of claim 1wherein an electrical signal path is closed when the pneumatic andelectrical connections between the first and second connection elementshave been established.
 7. The kit of claim 1 wherein the firstelectrical contact element comprises recesses into which matingprojections of the second electrical contact element are engageable toestablish electrical connection.
 8. The kit of claim 1 wherein theventilation tube includes a plurality of electrical lines.
 9. The kit ofclaim 8 wherein the electrical lines include a heating wire loop orcoil, a power supply line, a measurement line, or a data line.
 10. Thekit of claim 1 wherein the electrical line is a heating wire loop orcoil, a power supply line, a measurement line, or a data line.